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How Many Gpsr Units Will Not Project Waypoints?


GEO.JOE
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I have set up a cache that requires projecting a waypoint. I have already had some cachers contacting me because they can not find a way to project a waypoint. I have explained how to plot the point using their map page, however, by plotting the the waypoint on the map it can create a search area of 150 ft X 50 ft. That is a lot of area.

 

Are there many GPS units that can not project waypoints.

 

Also does anyone know if a Magellan Map 330 will project a waypoint?

 

Thanks

GEO.JOE

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The map 330 does, and most of the recent Magellan units (315/320, meridian's, sportrack's). I also believe most of the Garmin units project too.

 

Although I think Magellan and Garmin use different methods and the results are slightly different. So you may want to post a test example on here and see what people get with diffrent GPSr.

 

Wyatt W.

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Although I think Magellan and Garmin use different methods and the results are slightly different. So you may want to post a test example on here and see what people get with diffrent GPSr.

 

Wyatt W.

Thank you Wyatt for the suggestion.

 

Everyone Please project a Waypoint from

N37 05.882

W088 39.337

Project a waypoint at a bearing of 99 degrees at a distance of 1.82 miles.

 

I got a waypoint of

N37 05.635

W088 37.382

 

With a Garmin RINO 120

 

GEO.JOE

Edited by GEO.JOE
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Everyone Please project a Waypoint from

N37 05.882

W088 39.337

Project a waypoint at a bearing of 99 degrees at a distance of 1.82 miles.

 

I got a waypoint of

N37 05.635

W088 37.382

 

With a Garmin RINO 120

 

GEO.JOE

I hope I did this wrong.

Of the two garmins I found off hand, the gpsV said I should go to

37°05.637 88°37.403

while the etrex (gold/yellow) says

37°05.675 88°37.397 is the place <_<

IIRC the yellow go the project feature added during a firmware upgrade, were any of the people that couldn't do it using etrex with versions before 2.14 (thats what mine has).

 

Somewhere I have a legend, maybe I should try to find it and see what it says :)

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were any of the people that couldn't do it using etrex with versions before 2.14 (thats what mine has).

 

Both were using Magellans.

 

It is nice to see how accurate Projected waypoints are.

Yea, you should just tell them its a tree south of the parking lot.... <_<

 

And, the thing I forgot to ask in my last post, how are you getting two decimals for distance?? (I did 1.8mi but as you can tell even those two weren't that close together)

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were any of the people that couldn't do it using etrex with versions before 2.14 (thats what mine has).

 

Both were using Magellans.

 

It is nice to see how accurate Projected waypoints are.

Yea, you should just tell them its a tree south of the parking lot.... <_<

 

And, the thing I forgot to ask in my last post, how are you getting two decimals for distance?? (I did 1.8mi but as you can tell even those two weren't that close together)

Two decimals for distance is what The RINO gives. I would like to have it as accurate as feet.

 

I noticed that both of you waypoints were 1.80 mi the Etrex was at 98 degree according to my mapping software and the gpsV was at 99 degrees.

 

That adds a whole new dememtion of error. I thought that two decimals were too restrictive if many units only offer one decimal that could get a search area of about 150 ft X 260 ft.

 

I better raise the difficulty! :)

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I noticed that both of you waypoints were 1.80 mi the Etrex was at 98 degree according to my mapping software and the gpsV was at 99 degrees.

 

That adds a whole new dememtion of error. I thought that two decimals were too restrictive if many units only offer one decimal that could get a search area of about 150 ft X 260 ft.

 

I better raise the difficulty! <_<

yea they both only have one decimal (why is it you can never find the right toy when you want it?).

I redid the extrex and it came out the same location.

 

I did find one thing though, you don't say (and I didn't think to ask) if you want true or magnetic (or what degree of declination). One was set to true north and other was set to magnetic (auto?). Changing them both to same makes it much better (same for magnetic and only one digit for true, 637 403 637 404)!

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I've got one of the few Garmins that does not have waypoint projection (eMap).

So I converted the coordinates to UTM and then adjusted the easting by the distance (in m) times the sine of the angle and the northing by the distance times the cosine.

Converting back to lat/long gave me the projected waypoint at:

N 37 05.661'; W 88 37.380'

That was assuming the bearing was based on true north.

Of course this is based on the UTM grid which won't be quite aligned with the lat/long grid so I expected some discrepancy.

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Everyone Please project a Waypoint from

N37 05.882

W088 39.337

Project a waypoint at a bearing of 99 degrees at a distance of 1.82 miles.

 

I got a waypoint of

N37 05.635

W088 37.382

 

With a Garmin RINO 120

 

GEO.JOE

I hope I did this wrong.

Of the two garmins I found off hand, the gpsV said I should go to

37°05.637 88°37.403

while the etrex (gold/yellow) says

37°05.675 88°37.397 is the place :)

IIRC the yellow go the project feature added during a firmware upgrade, were any of the people that couldn't do it using etrex with versions before 2.14 (thats what mine has).

 

Somewhere I have a legend, maybe I should try to find it and see what it says :laughing:

Garmin 60CS

 

Magnetic

 

37°05.675 88°37.397

 

True

 

37°05.637 88°37.403

 

It does make a difference here in Kansas City. I suspect it would be different in other parts of the country. Our magnetic declination here is 003° East.

 

Brian

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I got these results projecting the bearing true north:

 

Legend:

37 05.635 N

88 37.382 W

 

Meridian:

37 05.634

88 37.379

 

GeoCalc Program:

Using "High Accuracy" setting:

37 05.634

88 37.385

 

Using "Great Circle" setting:

37 05.634

88 37.379

 

The Meridian and the GeoCalc on "Great Circle" setting gave the same results. The distance between the Legend and Meridian coords is about 16 feet.

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It does make a difference here in Kansas City. I suspect it would be different in other parts of the country. Our magnetic declination here is 003° East.

Yes, that's enough to mess up a projected waypoint, especially over a distance of over a mile. But it's still a small declination compared to much of the country.

 

I remember about 5 years ago one of Garmin's firmware releases applied the magnetic correction the wrong way to the route pointer. I called up their tech support and explained how the pointer was now giving the wrong direction whenever set to magnetic north. He called back a little later and said he tried it out in the Garmin parking lot in Olathe and didn't see the problem. Of course his pointer was only off by about 6 degrees which isn't too obvious. I was in an area with a 17 degree correction so the pointer was off by 34 degrees. I persuaded him to try it again after entering a large user-set value for the declination and that convinced him of the problem.

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I've got one of the few Garmins that does not have waypoint projection (eMap).

So I converted the coordinates to UTM and then adjusted the easting by the distance (in m) times the sine of the angle and the northing by the distance times the cosine.

Converting back to lat/long gave me the projected waypoint at:

N 37 05.661'; W 88 37.380'

That was assuming the bearing was based on true north.

Of course this is based on the UTM grid which won't be quite aligned with the lat/long grid so I expected some discrepancy.

:) That is about 159 ft from my projection. :laughing:

 

I'm not sure if it is worth the trouble. :lol:

 

I have forgotten to state that I used True North.

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I've got one of the few Garmins that does not have waypoint projection (eMap).

So I converted the coordinates to UTM and then adjusted the easting by the distance (in m) times the sine of the angle and the northing by the distance times the cosine.

Converting back to lat/long gave me the projected waypoint at:

N 37 05.661'; W 88 37.380'

That was assuming the bearing was based on true north.

Of course this is based on the UTM grid which won't be quite aligned with the lat/long grid so I expected some discrepancy.

So far only one GPS unit that does not project waypoints, are there more?

 

About half of the responses can only project to 1 decimal, which will place those individuals 106 ft too far.

 

Are there any other limitations to projecting waypoints?

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